Residents take shelter on a street after an earthquake in northwest China on July 22. / AFP/Getty Images

by Calum MacLeod, USA TODAY

by Calum MacLeod, USA TODAY

BEIJING â?? An earthquake rocked a rural, semi-arid area of northwestern China's Gansu province on Monday, killing at least 89 people and injuring hundreds more.

Another five people were listed as missing and 628 injured in the quake near the city of Dingxi in Gansu province. About 123,000 people were affected by the quake, with 31,600 people moved to temporary shelters, the provincial earthquake administration said on its website.

The first and strongest of a series of tremors struck at 7:45 a.m. Beijing time south of Dingxi, about 770 miles west of Beijing, toppling farmers' one-story homes and severing power lines. Nearly 2,000 homes were destroyed and about 22,500 damaged, the provincial government said.

That quake measured 6.6, followed by smaller tremors including a magnitude-5.6, according to the Chinese government. The U.S. Geological Survey measured the earlier quake as 5.9, at a relatively shallow depth of 6 miles. Quakes closer to the Earth's surface can cause heavier damage.

The Chinese Red Cross said it was shipping 200 tents, 1,000 sets of household items and 2,000 jackets to the area and also sending teams from both Lanzhou and Beijing to help with relief work and assess further needs. The hardest-hit areas were Min and Zhang counties, Chinese state media reported, and the epicenter fell between the two counties.

Heavy rains predicted for the next week could hamper rescue efforts and trigger secondary disasters such as landslides or building collapses. The area is not as heavily populated as many other parts of China. Its farmers sell their famous potatoes to clients worldwide, including U.S. fast-food giants KFC and McDonald's.

Many casualties have been reported in Meichuan township, where teacher Shu Mingming was washing his hair at home in Luzha village when the first tremor struck. "Suddenly the house was shaking violently, and several cracks appeared in the wall," Shu said.

"This is a tile-roofed, one-story house, and all the tiles were falling down. My daughter cried loudly, I quickly picked her up and went out. My hair was still wet. Luckily my wife and father escaped, too," he said.

After the earthquake, Shu said he rushed to his school, but no buildings had collapsed. "The kids are on holiday, and no teachers or staff were injured, so I felt relieved," he said.